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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

16 results found.

  1. VLA radio detection of GRB 081221
  2. VLA radio observation of GRB 081221
  3. GRB 081221: GROND observations
  4. GRB 081221: Probable host galaxy in Keck imaging
  5. GRB 081221, Swift-BAT refined analysis
  6. GRB 081222: Swift XRT refined analysis
  7. GRB081221: Fermi GBM observation
  8. Swift/UVOT observations of GRB 081221
  9. GRB 081221: Swift-XRT Refined Analysis
  10. GRB 081221: pseudo-redshift (pz=0.7) from the spectral parameters of the prompt emission
  11. GRB 081221: Gemini-N nIR imaging
  12. Konus-Wind observation of GRB 081221
  13. GRB 081221: Enhanced Swift-XRT position
  14. GRB 081221: further NOT observations
  15. GRB 081221: NOT observations
  16. GRB 081221: Swift detection of a burst

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